Kessler, R., & Sklar, A. (2009). In the president's secret service: Behind the scenes with agents in the line of fire and the presidents they protect (Unabridged.). Tantor Media.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Kessler, Ronald, و Alan Sklar. In the President's Secret Service: Behind the Scenes with Agents in the Line of Fire and the Presidents They Protect. Unabridged. Old Saybrook: Tantor Media, 2009.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Kessler, Ronald, و Alan Sklar. In the President's Secret Service: Behind the Scenes with Agents in the Line of Fire and the Presidents They Protect. Unabridged. Tantor Media, 2009.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.